Selective calling system.



M. P. GEBR a H. U.

will.

L .ma

M. F. GEBR L R. C. LEAKE4 SELECT-1v1, CALLING SYSTEM.

LPLICA'UN PIL) DTL. 30. 131], 1 119 692. j l L I L U Patented 119011914. g 3 SHEETSMSHEET 2.

"UNITED STATES raf-ranas ormoni,-

MA-URICE F. GEER AND RICHARD C. LEAKE, OF ROCHESTER, NEEV YORK, SSIGNORS T0 GENERAL RAILWAY SIGNAL COMPANY, 0F GATES, NEVI YORK, A CORPORATION 0F NEW YORK.

T0 all whom, it may concern;

Be it known that We, MAURICE F.GEER and- RICHARD C. LeAnn, citizens of the United States, and residents of the city' of Rochester, injthe county ofMonroe and State of New York, have invented a new and useful Selective Calling System, of which the following is a specification.'

lThis invention relates to a system which enables an operator at a central point to selectively call any one of a number of remote stations by thevuse of only two line wires, -sch a system is in the electrical art called a select-ivecalling system.

The primary object of the invention is to so construct and arrange a system vof the character described that all electrical energy needed for the operation of' the system can be supplied fromthe central station.

A further objectl o f the invention is to so arrange the system that the ultimate source of energy used in the system shall be a` source of low potential current which, heforeh'eing impressed upon the' line'wires to operate the selector device will, by means of a motor generator set or similar apparatus he translated into a current-of ,potential sufficiently high to'p erly operate the selec'- tors gat the-remote stations, thus permitting the employment of .a smallinuuhcr of cells of battery at'the central station withthe consequent dminution v of the Ytotal deterioration which would take place in the cells of battery at the central Station.

A further object of the invention is to so arrange thc system that the current supplied from the ultimate source used in the system will he of low potential, but by means 'of a translating device, such as a motor generator, it `"ill be changed into a current' of greater potential and it is an important object of this invention to so arrange the above mentioned units that any desired potential may bev derived from the motor generator.

A further object. of theinvention is to-so const-ructthe system that direct current may be used to operatethe selectors atthe remote stations, but either alternatingr or direct cu rrent may he used to cause the alarm to sound.

A further object of the invention is to so construct a system of the character described that a primary or secondary battery may be used to supply energy tgthesystcm,

Specification of Letters Patent.

` SELECTVE CALLING SYSTEM,

Patented Dec. 1, 1914.

Application filed December 30, 1910. Serial No. 609,083.

alternating current will Ahe,autoniaticaillvV set in operation by the firstact performed in making a call and will be automatie-.illyY disconnected at the tern'iination of the call.

A. further object of the invention is to se arrange the direct currcntgenerator that it n'ill 'automatically regulate the voltage sup plied to the line wires. i

A. further object ofthe invention is t/o so construct the system/ that an answer back final will `be given `at the central station when the alarm at the remote station sounds. i A

-i further object of the invention is to so construct and arrangea system of the character described that a-tclephone may beperinanently connected across' the line wires at the remote stations and that no means will here# uired to disconnect it during a period. of call. j

A further object. ofthe invention is to simplify the arrangements and constructions used in a system of the character de scribed and at the same time increase the reliability and decrease the cxpensiveness of the same.

Other objects and advantages will appear in the description of--ith'e system land its inode of operation and the novel features of the system will be particularly pointed out in the appended claims.

The invention consists'l ,in the combina` tions, arrangements and constructions herein shown, described and claimed.

At the present time there are two general methods in use for operating selective signalin systems, distinguished one from the other-iin' the mode of supplying electrical 'energy for the operation of the system. The iirst method, called the local energysvstem, employs batteries located at each starirn where a selector is located, for the purpose of supplying electrical energy for the operation of a signaling device which is central station for the purposp of supplying electrical energy; the second of which employs a continuously running generator, such the line may also fail.

as a dynamo or rotary converter for supplying electrical energy; the third of which employs a generator of some description which is started before a call is made, and stopped after the call is made. If primary batteries are used in either ofthese systems, a large expense for maintenance arises, for, whether in use or at rest, a primary battery constantly deteriorates and it has been found that both the local energy systems and the central energy systems employing primaryA batteries, are exceedingly expensive and of the two, the local energy system is the more expensive. If secondary batteries are used, the expense of maintaining the batteries should be decreased, but on the lother hand, whensecondary batteries are used, a large initial outlay is needed to install charging apparatus therewith, anda further constant expense for the services of a skilled attendant to attend the batteries, so-that the substitution of secondary batteries for primary batteries in a local energy system, although giving-more satisfactory results as far as operation is concerned, is really more expensive than the use of primary batteries.

n central energy schemes, secondary bat'-Y teries have been substituted for primary batteries with much better results, but due to the fact that a comparatively high voltage must be impressed upon the line wires of the system at the central station a large number of batteries must be installed, which necessitates a very large initial outlay and because ofthe Vfact that the amount of current re-I quired to operate the system is very slight,

the batteries are not discharged often enough to keep them in good condition, so that they deteriorate more rapidly than is sanctioned by good engineering practice.

if a generator is used in the central energy systems, it must be of such aty )e and be designed so rugged, that it'may lie run continuously '24 hours of the day and every day in the ycan, which, to one skilled` in the art means almost an impossibility, so that it is readily understood that duplicate apparatus must be installed which, of course, necessitates 'rery large initial outlay. lf a rotaryr rent de cate un (lili ed from a commercial line. duplippuratus does not entirely solve the fully for the means to furnish current to It has also been onverter is used, operatedby curfound that in such a system, the conny-v ously running apparatus must have .skilled attention, and as the ordinary operator ernratus, thus increasing the cost for maintenance. l y

Systems employii an intermittently running generatorl woud seein-to be the most practical method of operating a selective signaling system, but'iii practice such sysable than any of the others, for in making a call, employing suche. system, three operav'tems have been found'to be more objectiontions are necessary, first: the generator must be started and a lowed'to obtain sutlicient speed to generate suicient voltage; second;

the call must besent, and third: the. generator mustbe stopped. In'practice it has been found that' the firststep is very often neglected and as a consequence much loss of timecnsues and temper-s are not improved, and it has also been found that unless strict watch iskept upon the operators they will neglect to stop the generator after the call has beenmade in'order to do .away with the necessity of starting the. generator before the next call. lVhen such tricks are resorted to, the system and apparatus suffers severely for the generator not being designed to run continuously, soon wearsout and has to be replaced, and'furthermore, the cost for-electrical energy is very greatlyuincreased'so that it approaches very closely to those sys-A tems using lthe co-ntinuously .running generator. -Another difficulty with this 'system,v when the generator-.is allowed to rimixcontinf uously, arises from the fact that the'generator not being designed to run continuously and-,therefore not furnished in duplicate, as soon as it Wears out or breaks down, throws the entire system out of operation.

As a general conclusion it may be said that it has been found to be desirable in sys-. tems designed for continuous uninterrupted operation where electrical energy is einploycd to, if possible, depend in' the last in' stance upon-batteries.

In the case ofsystcins governing the movements of trains," which must act uninterruptedly and continuously all of the time, it has been found by experience extending over a long period of time, that for continuous and uninterrupted operation, reliance had best be placed upon batteries for furnishing electrical energy and forlthe same reason, a selective system which must also oper-'- ate continuously and uninterruptedly, should depend for its source of energy upon batteries, but at thesamev time the number of batteries should be such that they will be obliged to furnish sutlicient current to keep them in proper condition. Applicants have; therefore, devised a system of selective sigico 'I guppen nalin-g of such a character that batteries will be depended upon for a supply of electrical energy and the batteries are emplo ed in such number as to be economical. n applicants system, however, a means have been provided whereby the neglect of an operator to start the motor generator used to supply current before impulsos are attempted to be sent to the line is avoided and further means are provided whereby the motor generator is automatically stopped by the completion of the transmission of the current impulses, thus .entirely obviating all of the objections mentioned to heretofore devised systems'.

In describing the invention in detail ref erence is had to the accompanying draw- Y ings, wherein like reference characters denote corresponding 'parts through the several views, in which:

Figure 1 is `a diagram illustrating the wiring of the devices on the switch board and the wires leading therefrom. Fig. 2 is a diagram illustrating the wiring at the operators key, the line wires and one remote station connected therewith, Fig. 2 being a continuation of Fig. 1. Fig. 3 is a diagram illustrating the wiring at other remote stations, being a continuation of Fig. 2.

Construction-1 and 2 designate any suitable type of battery, being considered herein as secondary batteries; 3 and 4 desig nate 'wires connected to a suitable supply of energy ior charging secondary batteries 1 and 2, the system being so arranged that when one battery isbeing charged the other batt-ery is used to furnish current to the system and vice versa; 5 and 6 designate double pole ltwo throw switches which are used to connect and disconnect the batteries 1 and 2 with the charging lines 3 and 4l, the

switch 5 in the position shown connecting wire '7 from one pole of battery l to wire 3 and wire 8 from the other, pole of the bat tery 1 with wire 4, thus causing the battery to be charged. At the same time switch 6 connects the battery 2 by means of wires 9, 10, 11, coil 12, and wire 13 to the contact spring 14 at the transmitting key, and by meansA of wires 8 a; d 15 with the' contact spring 16. If the switches 5 and 6 are reversed one pole of battery 1 would be connected by means of `wire T, switch 5, wires 10 and 11, coil 12 and wire 13 to Contact sprin 14 and the other pole-of the battery woul be connected through wires 8 and 15 to contact spring 16. With the switches 5 and 6 in the last described position current from charging wire 4 would pass by means of switch 6 to wire 8 andso to battery, the other pole. of the battery being connected by wire 9 and switch 6 with the other charging wire lt is thus seen that while one attery is chargii'ig.` theother is con nected to the transmitting key, and vice versa, but if occasion demands both batteries may be connected in multiple to the transmitting key by throwing both switches 5 and 6 to the right, the circuit for battery 2 being as shown in Fig. l, and heretofore described, the circuit for battery 1 being as heretofore described with switch 5 thrown to the right to connect battery 1 with the transmitting key; 18 designates a relay having an armature 1,9, which bridges contacts 2O and 2l when th'e 'coil 12 is energized and the armature 19 is drawn upwardly. 'ln such position with switches 5 and 6 in the position shown a complete circuit is formed as follows: one pole of battery 2, wire 9, switch 6, wires 10 and 11, contact 20, armature 19, contact 21, wire to the motor M, passing in multiple through the armature 24 and field coil 25, uniting again and by wires 26 and 8 connecting with the other pole of the source 2. The motor armature 24 has on the same shaft with it the arlnature 27 of a direct current,generator G, which has a field 28 connected to wire 22 the other end of the field being connected by wire 29 to a rheostat 30, the movable arm of the rheostat being connected to Wire 31, which wire connects with Wire 8 and so to the other pole of the battery. Wire 22 always conveys the current to motor M and the field coil 28 of generator G for if switch 5 is thrown to the right to connect battery 1 to the transinitl'ng key and switch 6 is thrown to the lett to charge ,battery 2, then current from battery 1 can iow through wire T, switch and wire 10 to wire 11, contact 20, armature 19, contact 21 and wire 22; 32 designates a field coil on the generator, the two wires 33 and 34 connecting to the armature brushes and running to the transmitting key. On the saine shaft with armatures 2l and 27 are collector rings 35. These. collector rings are connected in the well known manner to the two ends of the wire wound on armature 27T so that while direct current may be obtained from brush 83 and the brush to which wire 3l is connected, alternating current may be obtained from rings 35. By means ot' Wire 3T and wire 38 through the condensers 40 one collector ring may be connected to both wires 33 and Si, and by means of wire llthe other collector ring may be connected to ground ll2; 43 designates any suitable electrical signal device in series with Wires 37 .and 3S.

V designates a voltmeter one side of which is connected to the wire 8 common to both batteries, the other side of which is connected to a, switch arm 41 adapted to make connection with either contact 45 or 46. `/ontact 4.6 by means oL wire 4T and wire 7 is connected to battery 1, while contact 45 by means of wire 48 and wire 9 is connectedv with battery 2, so that by placing arm 4:4 on one or the other of contacts 15 the batteries transmitting key T, fully shown, described and claimed in applicants co-pending application Serial No. 598,673 filed December 22nd, 1910.

Wires 49 and 50 lead from the metallic strips on the insulating disk to contact springs 51 and 52 respectively, which in the manner fully shown and described in the above' mentioned application are contacted at times by springs 53 and 54 to connect wires 49 and 50 with line wires 55 and 56 respectively.

S designates a Aselector device such as is shown described and claimed in applicants co-pending application Serial No. 596,252, led December 8, 1910, in which 58 and 59 designate the revoluble sectors actuated by means of armature 60 and arm 61 and dogs 62 and 63 to close contact between wire 64 and spring contact 65 and also between wire 76 and contact 77 at the same time if desired, as fully set forth in the above mentioned a plication Serial No. 596,252; 66 4'and 67 esignate the coils on the cores 68 and 69 which when a current is passed therethrough energizes cores 68 and 69 to oscillate armature 60; 76 designatesa non-inductive resistance by which the coils 67 and 66 are connected and which regulates the amount of current which can How through the selector; 64 designates a wire connected to the middle point of resistance 70, which by means of contact spring 65 wire 71,. condenser 72 and wire 73 is connected to analternating current bell B, the other side of the bell being connected to the ground at 42; 74 designates two springs forming the means for an all stations call as fullyset forth in my above mentioned application, being connected in multiple across the nor- 4mally open break between wire 64 and contact spring 65 or across the normally open break between wire 76 and contact 77, as shown at the right hand of Fig. 3; 75 designates a. telephone connected across the line" wires 55 and 56 by means of which communication is had with the central station.

Fig. 3 simply illustrates an extension of wires 55 and 56 showing two more remote stations connected across the line wires the only difference being that the resistances 76 and '77 are different in ohmie resistance from each other and from resistance in order to compensate for line losses, the station most distant `from the transmitter having the smallest resistance.

0pe1'atz'on.-, When an operator desires to call any oneJ of the stations at which the selectors S are placed, he first pushes a button which makes contact between wire 14 and spring 16 and simultaneously predetermines the number lof impulses of one polarity which will be sent to line wires 55 and 56, and also unlocks, the arm of the transmitter so that it may be turned in a.

spring 16 sends a current through the coil 12 from the battery 2 by virtue of the circuit heretofore described and causes a current from the battery 2 to pass through the motor M by a circuit heretofore described thus causing the motor armature to rotate and as the armature 27 of the generator G is connected to thc same shaft as the armature 24 of motor M it also rotates, and as the field 2,8 is energized from the battery 2 at the same time that motor M is caused to rotate a current is generated in the armature 27 of the generator G, which passes to wire 33 and through the field coil 32 connected therewith to the transinittin key, wire 34 connecting the other pole o the generator G with the transmitting ke .v So that ussoon as another key necessary or proper operation is depressed on the transmitter according to the manner fully explained in applicants eo-pending application, wires 49 and 50 will be connected with line wires 55 and 56 and the number of impulses of u certain polarity Ato be supplied to line wires 55 and 56 predetermined. A current will then pass out overone line wire throurh selector devices at the several stations and. return by the other line Wire and upenn rotation of the transmitter crank will cause the selectors at 'the remote stations to operate, but only one of them will so operate as to make a contact between wires 64 and spring 65 and wire 76 and spring 77. At the saine time a direct current was impressed upon the line wire an alternating current was enerated by armature 27 of generator G and y means of the collector ring 35 and the wires 37 and 38 was impressed upon both line wires through the condenseijs 40 and wires 33 and 34, and so as soon as contact is made between wire 64 and spring 65, at one of the stations the alternating current from one side of the source would pass along both line wires and from the line wires throii h the coils 66 and 67 of the selector,fand t en to the non-inductive resistance 70 passing from the central point of said resistance to Wire 64 to the springs 65 through thel condensers 72 to `wire 73 and then through the bell B to the iso right hand end of armature G0 to be raised.

from its normal horizontal position, thus vcausing dog to actuate sector' 58,'andfit has also been shown that direct current fof the reverse polarity causes the left hand end of armature GO to beraised and thus dog 65.3 and sector 59 to be actuated as armature 60 is polarized. It has further been shown that a proper combination of impulses in the two directions will so' actuate the sectors 58 and l59 as to close contact between springs 64 and 65 and 76 and 77. In ap lication Serial Number 598,673, hereto ore referred to it has been ullyshown and described how the transmitter 'by the revolution of the arm attached thereto `causes apredetermined numbemof impulses to be.

sent to the linein one direction and then automatically thereafter'cau'ses a predetermined number to be impressed `upon the line ofreverse polarityand also how thereafter a single impulse of the same polarity as the first impulses; is impressed upon the line to'hold the selector S in such a position that contact will be closed-between springs 64 and 65 and 76 and 77, and Ahow at the same time thealternating current from brush'36 flows through both'line-wires as a multiple circuit to and through theselector.at the called station Without valectin f itthrough contacts 6 4 and 65 to bell B anid to ground, returning by the ground to the transmitter' stationl and thence by.yvire 4.1 to the other brush 23 bearing on the other l collector ring.'

If the operator at the central station desires to call all remote stationssimultane;

ously, he would send out such number of impulses of the proper polarity as would cause the sector 58 to be rotated farther than it wouldbc rotated by any combination of impulses used to operate the selectors for individual call. lt would therefore make Contact between the springs 74v closing a bridging connection around wire 64: and contact spring 65, and ring the bell B, or if the bell 78 only were used, the,v springs 74 would be connected in multiple across the break 7G and 77 as shown at the right hand of Fig. 3, and so cause bell 78 to ring. It is to be observed that the con- -erned by the selective device, means intcluded in the transmitter whereby the opnectionV of one pole of the source of' alternating current to both line wires through thecondensers 40 does not short circuit the line Wires, as, it is impossible for direct current to pass through the condensers 40. It is also to be observed that the direct current which operates the vselectors at the different stations cannot pass through the bells B at the several stations b means of the condenser 72 in series wit the bell, as direct current cannot pass through the said condensers although a ternating current readily passes there-t rough. It is also to be observed that the resistances 70, 76 and 77 must be wound noninductively, for if they are not so wound it 'would be impossible for alternating current to flow through said resistances in order to actuat the bells B at the several stations.

Ve wish it' to be' understood that we do not desire to be` limited to the exact details of construction shown and described, for' obvious modifications will occur to .fa person skilled in the art.

Having particularly described the construction of one embodiment 'of ourv invention and explained the operation and principle thereof, what we claim as new' and desire to protect' by '.LettersPatent is 1. L1 a selectivejcalling system, normally denergized conductors, a s ource of' low potential current, Ia rotary.conve rter, -ia normally open -circuit connecting saidv` sourceand the motorjpartof the converter, a transmitting" device electrically connected to the generator part of the'rotaiy'fconyerter and to the conductors', a selectivejde'vice gov- `erned by the transmittin -device through the. conductor-sand an a arm device goveration of the transmitting device closes the said normally opencir'cuit and thusf'causes the operation of the' rotary coxglver'ten. and1 the alarm device. 1' j 2. In a selective calling system, a source of low potential electrical enerconductors. a rotary device adapted o transform said energy to a higher potential'` means for connecting said device to thes'aid conductor, said connecting means 'including mechanism adapted-to start said transforming means and'V to intermlttently impress said higher potential energy upon-thel conductors and at predetermined times change the polarity of the energy Asupplied to the conductors, a selector connected viith said-conductors', a contact closed by the acin series' bridged across said'conductors, contacts operated by said selector, an nullcator hai-ing two terminals one of which is connected to one 'of said contacts` the othery of said'contacts joined to the vconnection between said coils, another conductor, .the other terminal of said indicator connected to said other conductor, sources of both alternating and direct current, means to c onneet said first mentioned conductors with said source of direct current, and both of said first mentioned conductors with one terminal of--said source of alternating current, saidfotherlconductor being connected to the other terminal of the source of alternat? ing current.

4. In a selective signaling system, a source of low potential current, a transforming device adapted t'o at times transform the low potential current into a higher potential current, a central station and substations, lconductorsconnecting the central station with the substation's and the substations with each other, selectors at each of said stations except the central-station connected to said conductors, each of-said selectoxs comprising a--contact adapted to Be closed when the selector bearing it is suitably operated, an indicator at each of said substations, and means at the -central station adapted for setting said transforming device.

into operation and ,selectively operating said selectors, thereby closing said contact, a circuit closed by said contact-including said transforming device for supplying said indicator with energy from the central'y station Yto cause the indicator to indicate.

5. In a selective signaling system, two line wires, a return conductor; selectors in multiple circuit with the line wires; contacts operated by the selectors, indicators in series circuit with the contacts and in multiple with both line wires and the return conductor, a normally nactivesource of alternating current andof direct current, and means to cause said source to become active. break connected across the line witeqsaid selector' having contacts`adapted to be closed when said selector is selectively operated, a return conductor, an indicator Ahaving one ter-A minal connected through said contacts to both of said line wires, the other terminal of said indicatorl connected to said return conductor, condensers, one of said collector rings'conneeted through the condensers to both of said first mentioned two wires.

7. I n a selective signaling system, a source of current, a converter connected to said source in a normally open circuit, said con-4 verter having a motor side and a .generator .-5 side, the generator side having both collector rings and a commutator, a transmitter including means for closing and opening said normally open circuit, vline wires, two wires connected to the commutator through the transmitter to the line wires, a selector connected across the line wires, said selector having contacts adapted to be closed when said selector is selectively operated, a return conductor; Van indicator having one terminal connected through said contacts to both of said line wires, the other terminal of said indicator connected to said return conductor, condensers, one of said collector rings connected through the condensers to both of said first mentioned two wires` a signal device inseries with said; condensers and collector ring, the other of said collector rings connected to said return conductor.

8. In a selective signaling system, a source of current, a selector, a contact operated by the selector, an indicator controlled by the contact, a normally inactive converter arranged to generate b oth direct current and alternating current, means whereby the converter is connected to the source of current thereby causin the generation of botli alternating and direct current, means for causing the direct current to flow to the selector thereby actuating it, and operating the contact, a circuit completed by the operation of the contact whereby the alternating current-flows to the indicator thereby actuatmg it. A

9. In a'selective signaling system, a source of current, a selector, a contact operated by the select r, an indicator controlled by the contact,`ar normally inactive motor generator, means. whereby the motor generator is connected to the source' of current thereby causing the generation of current, means for causing the generated current to flow to the selector thereby actuatingfit 'and operating the Contact, a circuit completed by the operation ofthe contact whereby the generated 12o current flows to the indicator thereby actudevice governed by the transmitting device through the conductors andl an alarm device 1:5#

governed by the selective device. and means operating 1n unison withthe transmitter, adapted to close and open said normally oyen circuit, all so arranged that the operation of the transmitting device causes the operation of the converter and the alarm devlce.

11. vIn a selective calling system, normally denergized conductors, a source of current, a converter, a normaly open circuit connecting said source an converter, a transmittng device electrically connected to the converter and .to theconductors, a selective device governed by the transmitting device through the conductors and an alarm device governed by the selective device, and means operated in unison with the transmitter to govern the normally open switch to cause the converter to start and stop.

MAURICE F. GEEK. RICHARD C. LEAKE. Witnesses LiLLlAN L. PHILLIPS,

MARY G. DALBEY. 

